What is it?

A fully isolated USB to Serial adapter for communication and
also programming devices protecting your USB ports and connected devices.
Integrated hardware Autoreset function makes it suitable for direct
programming ESP8266, ESP32 and other MCU's that require it.
If you use
Arduino IDE/Platformio/etc for example with ESP8266, you will love it,
as it doesn't need to press anymore RST/Prog buttons for new sketch
upload! The autoreset function takes care of that, putting automatically
the ESP8266 module in the right boot mode.

Youtube Video step-by-step Tutorial on how to use it to program a ESP8266 Module:

In the case above ESP8266 is embedded on a MPRSx8 Home Automation board but in the same easy way can be used for programming standalone ESP8266 modules.

Pinout

Capabilities

Fully isolated interface

High speed (can work OK also at 115200 and up - used it with Arduino IDE/Platfromio at 921600)

DTR/RTS/autoreset function

2.5 kV RMS integrated digital isolator from Silicon Labs

High electromagnetic immunity

Ultra low power

Schmitt trigger inputs

Transient Immunity 50 kV/μs

Schematics

USB interface

Digital isolator

Auto-reset circuit

Below you can find also the wiring for the MPRSx8 Home Automation Board Programming: